Last year, researchers at The Osteopathic Research Center at the University of North Texas Health Science Center Texas College of Osteopathic Medicine reported their results of the largest osteopathic clinical trial to date, called the OSTEOPATHIC trial, which was a randomized, double-blind, sham-controlled study that demonstrated the efficacy of osteopathic manual treatment (more commonly known as osteopathic manipulative treatment [OMT]) for patients with chronic low back pain (LBP).1 In a subgroup analysis of that study reported last year,2 they found that patients with high baseline pain (defined as ≥50 mm on a 100-mm pain scale) responded significantly better than those with lower baseline pain. In this subgroup analysis of the same randomized clinical trial, the investigators assessed not only the clinical response to OMT vs sham therapy, but also the relapse rate following a series of OMT visits. This study is the first published report on the stability of patients' responses to OMT in a rigorously designed investigation.

This subgroup analysis included 186 participants (mean age, 43 years; 115 women [62%]) with high baseline pain. Fifty-five percent had LBP for more than 1 year. Participants received OMT or sham therapy and were assessed for clinical response at weeks 1, 2, 4, 6, 8, and 12. Fifty percent or greater pain reduction relative to baseline qualified as a substantial improvement in LBP. Sixty-two of 95 participants (65%) in the OMT group attained an initial clinical response, at a median time of 4 weeks, compared with 41 of 91 participants (45%) in the sham therapy group (RR, 1.45; 95% CI, 1.11-1.90). Typically, responding participants received 3 OMT sessions over a 4-week period. Relapse was greater in the sham group. There were 31 participants with an initial clinical response before week 12 that relapsed: 13 participants (24%) in the OMT group vs 18 (51%) in the sham therapy group (RR, 0.47; 95% CI, 0.26-0.83). Overall, 49 participants (52%) in the OMT group attained or maintained a clinical response at week 12 compared with 23 (25%) in the sham therapy group (RR, 2.04; 95% CI, 1.36-3.05). The authors commented that the large effect size for short-term efficacy of OMT was driven by stable responders who did not relapse.

This study demonstrates that after only 3 OMT sessions, a subgroup of patients with high baseline chronic LBP responded and maintained improvement for at least 3 months. These results help to answer a long-held research question as to what are the characteristics of patients that respond best to OMT.